Malicious PDF — malware analysis report

Static analysis result for SHA-256 6553be97db5e23c6…

MALICIOUS

PDF

111.8 KB Created: 2021-07-04 13:24:37 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 156db96b1fd361f0ab5529cbce133f6c SHA-1: 20aa35ff2ff2d18024531f5b3bf2390e74d1c541 SHA-256: 6553be97db5e23c610dcc2c5ec1edc216a6f675c299842f362589251572073b2
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF contains numerous links pointing to compromised WordPress sites, identified by heuristics as a 'link farm'. The ML classifier and ClamAV detection strongly indicate malicious intent, likely phishing or malware distribution. The document body is heavily obfuscated and unreadable, providing no direct clues to its purpose beyond the link farm structure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9866

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • Small PDF is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • External URI info PDF_URI
    PDF contains an external URL action
  • Object number defined twice with different bodies info PDF_DUPLICATE_OBJ_BODY_INCREMENTAL
    The same indirect object (N G) is defined more than once with different body bytes. First-wins and last-wins readers will resolve different content, which is a parser-confusion shape used by targeted PDFs. Body-only differences are common in benign incremental updates, so severity is raised only when the duplicate carries active content.
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL https://arizonapoolcontractor.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c22f9db85b6---73814586940.pdf
    • http://moda-minulosti.cz/docs/momin/file/10663823889.pdf
    • http://modelkyujin.com/wp-content/plugins/formcraft/file-upload/server/content/files/160989818417b6---rewenalubis.pdf
    • http://mountmedpharmacy.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/160c409d12e15e---85145740328.pdf
    • https://www.rowtheerne.com/wp-content/plugins/super-forms/uploads/php/files/1d356234f0d6344639fd2127707f8a32/moridafuwadujakivo.pdf
    • https://www.cukoyem.com.tr/wp-content/plugins/super-forms/uploads/php/files/ugread0d7213lesg47n6b4o480/lirefox.pdf
    • https://www.alignerco.ca/wp-content/plugins/super-forms/uploads/php/files/ebc4e5ded676d69aa1af915f39ec9bad/vufapiripavotexegowe.pdf
    • http://bagiez.de/userfiles/file/lewaraxerunefux.pdf
    • http://www.johnknox.ch/wp-content/plugins/formcraft/file-upload/server/content/files/160df46d3ebc12---zojemugukedufel.pdf
    • http://francisfamilyreunion.net/clients/870293/File/1298521066.pdf
    • http://anm-av.de/uploads/files/sozukemekumunoruwamo.pdf
    • http://distributoram.com/files/file/11137396623.pdf
    • http://saludocupacionalpso.com/home/wp-content/plugins/formcraft/file-upload/server/content/files/1609f2a24add55---59391588613.pdf
    • https://lokmangal.co.in/wp-content/plugins/super-forms/uploads/php/files/8d43261568606c63399798d2d3a0e348/rogetibogilo.pdf
    • http://www.itbaloch.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607f6459c9aab---41248603103.pdf
    • https://www.elitelawnsolutions.co.uk/wp-content/plugins/super-forms/uploads/php/files/m5cc4andpnhrim8ra79mqh1u02/51460711617.pdf
    • https://sca-kc.net/scauserfiles/files/85388137414.pdf
    • http://cerezolorente.com/files/cerezolorente/_repo/file/11238305376.pdf
    • http://okuninka-biale.pl/userfiles/file/90032762904.pdf
    • http://m-camper.ru/ckfinder/userfiles/files/1686361613.pdf
    • https://alshamiltrading.com/alshamilfiles/file/96168688773.pdf
    • http://www.goataxiservice.com/wp-content/plugins/formcraft/file-upload/server/content/files/16085371ba3ec9---jevumu.pdf
    • https://jnfarley.com/wp-content/plugins/super-forms/uploads/php/files/58mpv5scbk5mfrlmo465lc3fn6/46199712200.pdf
    • https://thejinglelab.com/wp-content/plugins/super-forms/uploads/php/files/jskq1dmc3t0414h4kro1235187/dotiponi.pdf
    • http://tele-fonika.pl/upload/file/29751003118.pdf
    • https://soudurelauziere.com/upload/editor/file/71350837512.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/ngfLrbzwjls/uplcv?utm_term=rational+and+non+rational+decision+making
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0001559f.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x1559F 16792 bytes
font_01_sfnt_off00016db1.bin
a6353f11bc80b35786d21a1303d21c32d5b845552fcdd83f4dae1dfcdebdcfbf
pdf-font-stream PDF embedded font (sfnt) at offset 0x16DB1 16556 bytes
font_02_sfnt_off0001987b.bin
5c42eef00c713559b37c9ff1d26b66a39e4fd8fcb29074d0f2c23987d3071015
pdf-font-stream PDF embedded font (sfnt) at offset 0x1987B 10848 bytes